diff options
Diffstat (limited to 'net/ipv4/tcp_minisocks.c')
| -rw-r--r-- | net/ipv4/tcp_minisocks.c | 296 |
1 files changed, 204 insertions, 92 deletions
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index e002f2e1d4f2..bd5462154f97 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -20,8 +20,11 @@ */ #include <net/tcp.h> +#include <net/tcp_ecn.h> #include <net/xfrm.h> #include <net/busy_poll.h> +#include <net/rstreason.h> +#include <net/psp.h> static bool tcp_in_window(u32 seq, u32 end_seq, u32 s_win, u32 e_win) { @@ -43,7 +46,7 @@ tcp_timewait_check_oow_rate_limit(struct inet_timewait_sock *tw, /* Send ACK. Note, we do not put the bucket, * it will be released by caller. */ - return TCP_TW_ACK; + return TCP_TW_ACK_OOW; } /* We are rate-limiting, so just release the tw sock and drop skb. */ @@ -51,6 +54,19 @@ tcp_timewait_check_oow_rate_limit(struct inet_timewait_sock *tw, return TCP_TW_SUCCESS; } +static void twsk_rcv_nxt_update(struct tcp_timewait_sock *tcptw, u32 seq, + u32 rcv_nxt) +{ +#ifdef CONFIG_TCP_AO + struct tcp_ao_info *ao; + + ao = rcu_dereference(tcptw->ao_info); + if (unlikely(ao && seq < rcv_nxt)) + WRITE_ONCE(ao->rcv_sne, ao->rcv_sne + 1); +#endif + WRITE_ONCE(tcptw->tw_rcv_nxt, seq); +} + /* * * Main purpose of TIME-WAIT state is to close connection gracefully, * when one of ends sits in LAST-ACK or CLOSING retransmitting FIN @@ -83,45 +99,59 @@ tcp_timewait_check_oow_rate_limit(struct inet_timewait_sock *tw, */ enum tcp_tw_status tcp_timewait_state_process(struct inet_timewait_sock *tw, struct sk_buff *skb, - const struct tcphdr *th) + const struct tcphdr *th, u32 *tw_isn, + enum skb_drop_reason *drop_reason) { - struct tcp_options_received tmp_opt; struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw); + u32 rcv_nxt = READ_ONCE(tcptw->tw_rcv_nxt); + struct tcp_options_received tmp_opt; + enum skb_drop_reason psp_drop; bool paws_reject = false; + int ts_recent_stamp; + + /* Instead of dropping immediately, wait to see what value is + * returned. We will accept a non psp-encapsulated syn in the + * case where TCP_TW_SYN is returned. + */ + psp_drop = psp_twsk_rx_policy_check(tw, skb); tmp_opt.saw_tstamp = 0; - if (th->doff > (sizeof(*th) >> 2) && tcptw->tw_ts_recent_stamp) { + ts_recent_stamp = READ_ONCE(tcptw->tw_ts_recent_stamp); + if (th->doff > (sizeof(*th) >> 2) && ts_recent_stamp) { tcp_parse_options(twsk_net(tw), skb, &tmp_opt, 0, NULL); if (tmp_opt.saw_tstamp) { if (tmp_opt.rcv_tsecr) tmp_opt.rcv_tsecr -= tcptw->tw_ts_offset; - tmp_opt.ts_recent = tcptw->tw_ts_recent; - tmp_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp; + tmp_opt.ts_recent = READ_ONCE(tcptw->tw_ts_recent); + tmp_opt.ts_recent_stamp = ts_recent_stamp; paws_reject = tcp_paws_reject(&tmp_opt, th->rst); } } - if (tw->tw_substate == TCP_FIN_WAIT2) { + if (READ_ONCE(tw->tw_substate) == TCP_FIN_WAIT2) { /* Just repeat all the checks of tcp_rcv_state_process() */ + if (psp_drop) + goto out_put; + /* Out of window, send ACK */ if (paws_reject || !tcp_in_window(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq, - tcptw->tw_rcv_nxt, - tcptw->tw_rcv_nxt + tcptw->tw_rcv_wnd)) + rcv_nxt, + rcv_nxt + tcptw->tw_rcv_wnd)) return tcp_timewait_check_oow_rate_limit( tw, skb, LINUX_MIB_TCPACKSKIPPEDFINWAIT2); if (th->rst) goto kill; - if (th->syn && !before(TCP_SKB_CB(skb)->seq, tcptw->tw_rcv_nxt)) + if (th->syn && !before(TCP_SKB_CB(skb)->seq, rcv_nxt)) return TCP_TW_RST; /* Dup ACK? */ if (!th->ack || - !after(TCP_SKB_CB(skb)->end_seq, tcptw->tw_rcv_nxt) || + !after(TCP_SKB_CB(skb)->end_seq, rcv_nxt) || TCP_SKB_CB(skb)->end_seq == TCP_SKB_CB(skb)->seq) { inet_twsk_put(tw); return TCP_TW_SUCCESS; @@ -131,15 +161,22 @@ tcp_timewait_state_process(struct inet_timewait_sock *tw, struct sk_buff *skb, * reset. */ if (!th->fin || - TCP_SKB_CB(skb)->end_seq != tcptw->tw_rcv_nxt + 1) + TCP_SKB_CB(skb)->end_seq != rcv_nxt + 1) return TCP_TW_RST; /* FIN arrived, enter true time-wait state. */ - tw->tw_substate = TCP_TIME_WAIT; - tcptw->tw_rcv_nxt = TCP_SKB_CB(skb)->end_seq; + WRITE_ONCE(tw->tw_substate, TCP_TIME_WAIT); + twsk_rcv_nxt_update(tcptw, TCP_SKB_CB(skb)->end_seq, + rcv_nxt); + if (tmp_opt.saw_tstamp) { - tcptw->tw_ts_recent_stamp = ktime_get_seconds(); - tcptw->tw_ts_recent = tmp_opt.rcv_tsval; + u64 ts = tcp_clock_ms(); + + WRITE_ONCE(tw->tw_entry_stamp, ts); + WRITE_ONCE(tcptw->tw_ts_recent_stamp, + div_u64(ts, MSEC_PER_SEC)); + WRITE_ONCE(tcptw->tw_ts_recent, + tmp_opt.rcv_tsval); } inet_twsk_reschedule(tw, TCP_TIMEWAIT_LEN); @@ -164,10 +201,13 @@ tcp_timewait_state_process(struct inet_timewait_sock *tw, struct sk_buff *skb, */ if (!paws_reject && - (TCP_SKB_CB(skb)->seq == tcptw->tw_rcv_nxt && + (TCP_SKB_CB(skb)->seq == rcv_nxt && (TCP_SKB_CB(skb)->seq == TCP_SKB_CB(skb)->end_seq || th->rst))) { /* In window segment, it may be only reset or bare ack. */ + if (psp_drop) + goto out_put; + if (th->rst) { /* This is TIME_WAIT assassination, in two flavors. * Oh well... nobody has a sufficient solution to this @@ -183,8 +223,10 @@ kill: } if (tmp_opt.saw_tstamp) { - tcptw->tw_ts_recent = tmp_opt.rcv_tsval; - tcptw->tw_ts_recent_stamp = ktime_get_seconds(); + WRITE_ONCE(tcptw->tw_ts_recent, + tmp_opt.rcv_tsval); + WRITE_ONCE(tcptw->tw_ts_recent_stamp, + ktime_get_seconds()); } inet_twsk_put(tw); @@ -209,18 +251,23 @@ kill: */ if (th->syn && !th->rst && !th->ack && !paws_reject && - (after(TCP_SKB_CB(skb)->seq, tcptw->tw_rcv_nxt) || + (after(TCP_SKB_CB(skb)->seq, rcv_nxt) || (tmp_opt.saw_tstamp && - (s32)(tcptw->tw_ts_recent - tmp_opt.rcv_tsval) < 0))) { + (s32)(READ_ONCE(tcptw->tw_ts_recent) - tmp_opt.rcv_tsval) < 0))) { u32 isn = tcptw->tw_snd_nxt + 65535 + 2; if (isn == 0) isn++; - TCP_SKB_CB(skb)->tcp_tw_isn = isn; + *tw_isn = isn; return TCP_TW_SYN; } - if (paws_reject) - __NET_INC_STATS(twsk_net(tw), LINUX_MIB_PAWSESTABREJECTED); + if (psp_drop) + goto out_put; + + if (paws_reject) { + *drop_reason = SKB_DROP_REASON_TCP_RFC7323_TW_PAWS; + __NET_INC_STATS(twsk_net(tw), LINUX_MIB_PAWS_TW_REJECTED); + } if (!th->rst) { /* In this case we must reset the TIMEWAIT timer. @@ -235,10 +282,12 @@ kill: return tcp_timewait_check_oow_rate_limit( tw, skb, LINUX_MIB_TCPACKSKIPPEDTIMEWAIT); } + +out_put: inet_twsk_put(tw); return TCP_TW_SUCCESS; } -EXPORT_SYMBOL(tcp_timewait_state_process); +EXPORT_IPV6_MOD(tcp_timewait_state_process); static void tcp_time_wait_init(struct sock *sk, struct tcp_timewait_sock *tcptw) { @@ -261,8 +310,6 @@ static void tcp_time_wait_init(struct sock *sk, struct tcp_timewait_sock *tcptw) tcptw->tw_md5_key = kmemdup(key, sizeof(*key), GFP_ATOMIC); if (!tcptw->tw_md5_key) return; - if (!tcp_alloc_md5sig_pool()) - goto out_free; if (!static_key_fast_inc_not_disabled(&tcp_md5_needed.key.key)) goto out_free; } @@ -280,7 +327,7 @@ out_free: void tcp_time_wait(struct sock *sk, int state, int timeo) { const struct inet_connection_sock *icsk = inet_csk(sk); - const struct tcp_sock *tp = tcp_sk(sk); + struct tcp_sock *tp = tcp_sk(sk); struct net *net = sock_net(sk); struct inet_timewait_sock *tw; @@ -289,20 +336,26 @@ void tcp_time_wait(struct sock *sk, int state, int timeo) if (tw) { struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw); const int rto = (icsk->icsk_rto << 2) - (icsk->icsk_rto >> 1); - struct inet_sock *inet = inet_sk(sk); - tw->tw_transparent = inet->transparent; tw->tw_mark = sk->sk_mark; - tw->tw_priority = sk->sk_priority; + tw->tw_priority = READ_ONCE(sk->sk_priority); tw->tw_rcv_wscale = tp->rx_opt.rcv_wscale; + /* refreshed when we enter true TIME-WAIT state */ + tw->tw_entry_stamp = tcp_time_stamp_ms(tp); tcptw->tw_rcv_nxt = tp->rcv_nxt; tcptw->tw_snd_nxt = tp->snd_nxt; tcptw->tw_rcv_wnd = tcp_receive_window(tp); tcptw->tw_ts_recent = tp->rx_opt.ts_recent; tcptw->tw_ts_recent_stamp = tp->rx_opt.ts_recent_stamp; tcptw->tw_ts_offset = tp->tsoffset; + tw->tw_usec_ts = tp->tcp_usec_ts; tcptw->tw_last_oow_ack_time = 0; tcptw->tw_tx_delay = tp->tcp_tx_delay; + tw->tw_txhash = sk->sk_txhash; + tw->tw_tx_queue_mapping = sk->sk_tx_queue_mapping; +#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING + tw->tw_rx_queue_mapping = sk->sk_rx_queue_mapping; +#endif #if IS_ENABLED(CONFIG_IPV6) if (tw->tw_family == PF_INET6) { struct ipv6_pinfo *np = inet6_sk(sk); @@ -311,12 +364,12 @@ void tcp_time_wait(struct sock *sk, int state, int timeo) tw->tw_v6_rcv_saddr = sk->sk_v6_rcv_saddr; tw->tw_tclass = np->tclass; tw->tw_flowlabel = be32_to_cpu(np->flow_label & IPV6_FLOWLABEL_MASK); - tw->tw_txhash = sk->sk_txhash; tw->tw_ipv6only = sk->sk_ipv6only; } #endif tcp_time_wait_init(sk, tcptw); + tcp_ao_time_wait(tcptw, tp); /* Get the TIME_WAIT timeout firing. */ if (timeo < rto) @@ -325,17 +378,10 @@ void tcp_time_wait(struct sock *sk, int state, int timeo) if (state == TCP_TIME_WAIT) timeo = TCP_TIMEWAIT_LEN; - /* tw_timer is pinned, so we need to make sure BH are disabled - * in following section, otherwise timer handler could run before - * we complete the initialization. - */ - local_bh_disable(); - inet_twsk_schedule(tw, timeo); /* Linkage updates. * Note that access to tw after this point is illegal. */ - inet_twsk_hashdance(tw, sk, net->ipv4.tcp_death_row.hashinfo); - local_bh_enable(); + inet_twsk_hashdance_schedule(tw, sk, net->ipv4.tcp_death_row.hashinfo, timeo); } else { /* Sorry, if we're out of memory, just CLOSE this * socket up. We've got bigger problems than @@ -356,15 +402,16 @@ void tcp_twsk_destructor(struct sock *sk) struct tcp_timewait_sock *twsk = tcp_twsk(sk); if (twsk->tw_md5_key) { - kfree_rcu(twsk->tw_md5_key, rcu); + kfree(twsk->tw_md5_key); static_branch_slow_dec_deferred(&tcp_md5_needed); } } #endif + tcp_ao_destroy_sock(sk, true); + psp_twsk_assoc_free(inet_twsk(sk)); } -EXPORT_SYMBOL_GPL(tcp_twsk_destructor); -void tcp_twsk_purge(struct list_head *net_exit_list, int family) +void tcp_twsk_purge(struct list_head *net_exit_list) { bool purged_once = false; struct net *net; @@ -372,18 +419,13 @@ void tcp_twsk_purge(struct list_head *net_exit_list, int family) list_for_each_entry(net, net_exit_list, exit_list) { if (net->ipv4.tcp_death_row.hashinfo->pernet) { /* Even if tw_refcount == 1, we must clean up kernel reqsk */ - inet_twsk_purge(net->ipv4.tcp_death_row.hashinfo, family); + inet_twsk_purge(net->ipv4.tcp_death_row.hashinfo); } else if (!purged_once) { - /* The last refcount is decremented in tcp_sk_exit_batch() */ - if (refcount_read(&net->ipv4.tcp_death_row.tw_refcount) == 1) - continue; - - inet_twsk_purge(&tcp_hashinfo, family); + inet_twsk_purge(&tcp_hashinfo); purged_once = true; } } } -EXPORT_SYMBOL_GPL(tcp_twsk_purge); /* Warning : This function is called without sk_listener being locked. * Be sure to read socket fields once, as their value could change under us. @@ -426,12 +468,27 @@ void tcp_openreq_init_rwin(struct request_sock *req, rcv_wnd); ireq->rcv_wscale = rcv_wscale; } -EXPORT_SYMBOL(tcp_openreq_init_rwin); -static void tcp_ecn_openreq_child(struct tcp_sock *tp, - const struct request_sock *req) +static void tcp_ecn_openreq_child(struct sock *sk, + const struct request_sock *req, + const struct sk_buff *skb) { - tp->ecn_flags = inet_rsk(req)->ecn_ok ? TCP_ECN_OK : 0; + const struct tcp_request_sock *treq = tcp_rsk(req); + struct tcp_sock *tp = tcp_sk(sk); + + if (treq->accecn_ok) { + tcp_ecn_mode_set(tp, TCP_ECN_MODE_ACCECN); + tp->syn_ect_snt = treq->syn_ect_snt; + tcp_accecn_third_ack(sk, skb, treq->syn_ect_snt); + tp->saw_accecn_opt = treq->saw_accecn_opt; + tp->prev_ecnfield = treq->syn_ect_rcv; + tp->accecn_opt_demand = 1; + tcp_ecn_received_counters_payload(sk, skb); + } else { + tcp_ecn_mode_set(tp, inet_rsk(req)->ecn_ok ? + TCP_ECN_MODE_RFC3168 : + TCP_ECN_DISABLED); + } } void tcp_ca_openreq_child(struct sock *sk, const struct dst_entry *dst) @@ -461,9 +518,9 @@ void tcp_ca_openreq_child(struct sock *sk, const struct dst_entry *dst) tcp_set_ca_state(sk, TCP_CA_Open); } -EXPORT_SYMBOL_GPL(tcp_ca_openreq_child); +EXPORT_IPV6_MOD_GPL(tcp_ca_openreq_child); -static void smc_check_reset_syn_req(struct tcp_sock *oldtp, +static void smc_check_reset_syn_req(const struct tcp_sock *oldtp, struct request_sock *req, struct tcp_sock *newtp) { @@ -492,7 +549,8 @@ struct sock *tcp_create_openreq_child(const struct sock *sk, const struct inet_request_sock *ireq = inet_rsk(req); struct tcp_request_sock *treq = tcp_rsk(req); struct inet_connection_sock *newicsk; - struct tcp_sock *oldtp, *newtp; + const struct tcp_sock *oldtp; + struct tcp_sock *newtp; u32 seq; if (!newsk) @@ -527,15 +585,14 @@ struct sock *tcp_create_openreq_child(const struct sock *sk, newicsk->icsk_ack.lrcvtime = tcp_jiffies32; newtp->lsndtime = tcp_jiffies32; - newsk->sk_txhash = treq->txhash; + newsk->sk_txhash = READ_ONCE(treq->txhash); newtp->total_retrans = req->num_retrans; tcp_init_xmit_timers(newsk); WRITE_ONCE(newtp->write_seq, newtp->pushed_seq = treq->snt_isn + 1); if (sock_flag(newsk, SOCK_KEEPOPEN)) - inet_csk_reset_keepalive_timer(newsk, - keepalive_time_when(newtp)); + tcp_reset_keepalive_timer(newsk, keepalive_time_when(newtp)); newtp->rx_opt.tstamp_ok = ireq->tstamp_ok; newtp->rx_opt.sack_ok = ireq->sack_ok; @@ -554,28 +611,49 @@ struct sock *tcp_create_openreq_child(const struct sock *sk, newtp->max_window = newtp->snd_wnd; if (newtp->rx_opt.tstamp_ok) { + newtp->tcp_usec_ts = treq->req_usec_ts; newtp->rx_opt.ts_recent = req->ts_recent; newtp->rx_opt.ts_recent_stamp = ktime_get_seconds(); newtp->tcp_header_len = sizeof(struct tcphdr) + TCPOLEN_TSTAMP_ALIGNED; } else { + newtp->tcp_usec_ts = 0; newtp->rx_opt.ts_recent_stamp = 0; newtp->tcp_header_len = sizeof(struct tcphdr); } if (req->num_timeout) { + newtp->total_rto = req->num_timeout; newtp->undo_marker = treq->snt_isn; - newtp->retrans_stamp = div_u64(treq->snt_synack, - USEC_PER_SEC / TCP_TS_HZ); + if (newtp->tcp_usec_ts) { + newtp->retrans_stamp = treq->snt_synack; + newtp->total_rto_time = (u32)(tcp_clock_us() - + newtp->retrans_stamp) / USEC_PER_MSEC; + } else { + newtp->retrans_stamp = div_u64(treq->snt_synack, + USEC_PER_SEC / TCP_TS_HZ); + newtp->total_rto_time = tcp_clock_ms() - + newtp->retrans_stamp; + } + newtp->total_rto_recoveries = 1; } newtp->tsoffset = treq->ts_off; #ifdef CONFIG_TCP_MD5SIG newtp->md5sig_info = NULL; /*XXX*/ - if (treq->af_specific->req_md5_lookup(sk, req_to_sk(req))) - newtp->tcp_header_len += TCPOLEN_MD5SIG_ALIGNED; #endif +#ifdef CONFIG_TCP_AO + newtp->ao_info = NULL; + + if (tcp_rsk_used_ao(req)) { + struct tcp_ao_key *ao_key; + + ao_key = treq->af_specific->ao_lookup(sk, req, tcp_rsk(req)->ao_keyid, -1); + if (ao_key) + newtp->tcp_header_len += tcp_ao_len_aligned(ao_key); + } + #endif if (skb->len >= TCP_MSS_DEFAULT + newtp->tcp_header_len) newicsk->icsk_ack.last_seg_size = skb->len - newtp->tcp_header_len; newtp->rx_opt.mss_clamp = req->mss; - tcp_ecn_openreq_child(newtp, req); + tcp_ecn_openreq_child(newsk, req, skb); newtp->fastopen_req = NULL; RCU_INIT_POINTER(newtp->fastopen_rsk, NULL); @@ -584,6 +662,8 @@ struct sock *tcp_create_openreq_child(const struct sock *sk, __TCP_INC_STATS(sock_net(sk), TCP_MIB_PASSIVEOPENS); + xa_init_flags(&newsk->sk_user_frags, XA_FLAGS_ALLOC1); + return newsk; } EXPORT_SYMBOL(tcp_create_openreq_child); @@ -597,32 +677,44 @@ EXPORT_SYMBOL(tcp_create_openreq_child); * validation and inside tcp_v4_reqsk_send_ack(). Can we do better? * * We don't need to initialize tmp_opt.sack_ok as we don't use the results + * + * Note: If @fastopen is true, this can be called from process context. + * Otherwise, this is from BH context. */ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, struct request_sock *req, - bool fastopen, bool *req_stolen) + bool fastopen, bool *req_stolen, + enum skb_drop_reason *drop_reason) { struct tcp_options_received tmp_opt; struct sock *child; const struct tcphdr *th = tcp_hdr(skb); __be32 flg = tcp_flag_word(th) & (TCP_FLAG_RST|TCP_FLAG_SYN|TCP_FLAG_ACK); + bool tsecr_reject = false; bool paws_reject = false; bool own_req; tmp_opt.saw_tstamp = 0; + tmp_opt.accecn = 0; if (th->doff > (sizeof(struct tcphdr)>>2)) { tcp_parse_options(sock_net(sk), skb, &tmp_opt, 0, NULL); if (tmp_opt.saw_tstamp) { tmp_opt.ts_recent = req->ts_recent; - if (tmp_opt.rcv_tsecr) + if (tmp_opt.rcv_tsecr) { + if (inet_rsk(req)->tstamp_ok && !fastopen) + tsecr_reject = !between(tmp_opt.rcv_tsecr, + tcp_rsk(req)->snt_tsval_first, + READ_ONCE(tcp_rsk(req)->snt_tsval_last)); tmp_opt.rcv_tsecr -= tcp_rsk(req)->ts_off; + } /* We do not store true stamp, but it is not required, * it can be estimated (approximately) * from another data. */ - tmp_opt.ts_recent_stamp = ktime_get_seconds() - reqsk_timeout(req, TCP_RTO_MAX) / HZ; + tmp_opt.ts_recent_stamp = ktime_get_seconds() - + tcp_reqsk_timeout(req) / HZ; paws_reject = tcp_paws_reject(&tmp_opt, th->rst); } } @@ -658,10 +750,10 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, LINUX_MIB_TCPACKSKIPPEDSYNRECV, &tcp_rsk(req)->last_oow_ack_time) && - !inet_rtx_syn_ack(sk, req)) { + !tcp_rtx_synack(sk, req)) { unsigned long expires = jiffies; - expires += reqsk_timeout(req, TCP_RTO_MAX); + expires += tcp_reqsk_timeout(req); if (!fastopen) mod_timer_pending(&req->rsk_timer, expires); else @@ -732,31 +824,34 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, tcp_rsk(req)->snt_isn + 1)) return sk; - /* Also, it would be not so bad idea to check rcv_tsecr, which - * is essentially ACK extension and too early or too late values - * should cause reset in unsynchronized states. - */ - /* RFC793: "first check sequence number". */ - if (paws_reject || !tcp_in_window(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq, - tcp_rsk(req)->rcv_nxt, tcp_rsk(req)->rcv_nxt + req->rsk_rcv_wnd)) { + if (paws_reject || tsecr_reject || + !tcp_in_window(TCP_SKB_CB(skb)->seq, + TCP_SKB_CB(skb)->end_seq, + tcp_rsk(req)->rcv_nxt, + tcp_rsk(req)->rcv_nxt + + tcp_synack_window(req))) { /* Out of window: send ACK and drop. */ if (!(flg & TCP_FLAG_RST) && !tcp_oow_rate_limited(sock_net(sk), skb, LINUX_MIB_TCPACKSKIPPEDSYNRECV, &tcp_rsk(req)->last_oow_ack_time)) req->rsk_ops->send_ack(sk, skb, req); - if (paws_reject) - __NET_INC_STATS(sock_net(sk), LINUX_MIB_PAWSESTABREJECTED); + if (paws_reject) { + SKB_DR_SET(*drop_reason, TCP_RFC7323_PAWS); + NET_INC_STATS(sock_net(sk), LINUX_MIB_PAWSESTABREJECTED); + } else if (tsecr_reject) { + SKB_DR_SET(*drop_reason, TCP_RFC7323_TSECR); + NET_INC_STATS(sock_net(sk), LINUX_MIB_TSECRREJECTED); + } else { + SKB_DR_SET(*drop_reason, TCP_OVERWINDOW); + } return NULL; } /* In sequence, PAWS is OK. */ - if (tmp_opt.saw_tstamp && !after(TCP_SKB_CB(skb)->seq, tcp_rsk(req)->rcv_nxt)) - req->ts_recent = tmp_opt.rcv_tsval; - if (TCP_SKB_CB(skb)->seq == tcp_rsk(req)->rcv_isn) { /* Truncate SYN, it is out of window starting at tcp_rsk(req)->rcv_isn + 1. */ @@ -767,7 +862,7 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, * "fourth, check the SYN bit" */ if (flg & (TCP_FLAG_RST|TCP_FLAG_SYN)) { - __TCP_INC_STATS(sock_net(sk), TCP_MIB_ATTEMPTFAILS); + TCP_INC_STATS(sock_net(sk), TCP_MIB_ATTEMPTFAILS); goto embryonic_reset; } @@ -780,6 +875,18 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, if (!(flg & TCP_FLAG_ACK)) return NULL; + if (tcp_rsk(req)->accecn_ok && tmp_opt.accecn && + tcp_rsk(req)->saw_accecn_opt < TCP_ACCECN_OPT_COUNTER_SEEN) { + u8 saw_opt = tcp_accecn_option_init(skb, tmp_opt.accecn); + + tcp_rsk(req)->saw_accecn_opt = saw_opt; + if (tcp_rsk(req)->saw_accecn_opt == TCP_ACCECN_OPT_FAIL_SEEN) { + u8 fail_mode = TCP_ACCECN_OPT_FAIL_RECV; + + tcp_rsk(req)->accecn_fail_mode |= fail_mode; + } + } + /* For Fast Open no more processing is needed (sk is the * child socket). */ @@ -787,7 +894,7 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, return sk; /* While TCP_DEFER_ACCEPT is active, drop bare ACK. */ - if (req->num_timeout < inet_csk(sk)->icsk_accept_queue.rskq_defer_accept && + if (req->num_timeout < READ_ONCE(inet_csk(sk)->icsk_accept_queue.rskq_defer_accept) && TCP_SKB_CB(skb)->end_seq == tcp_rsk(req)->rcv_isn + 1) { inet_rsk(req)->acked = 1; __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPDEFERACCEPTDROP); @@ -805,6 +912,10 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, if (!child) goto listen_overflow; + if (own_req && tmp_opt.saw_tstamp && + !after(TCP_SKB_CB(skb)->seq, tcp_rsk(req)->rcv_nxt)) + tcp_sk(child)->rx_opt.ts_recent = tmp_opt.rcv_tsval; + if (own_req && rsk_drop_req(req)) { reqsk_queue_removed(&inet_csk(req->rsk_listener)->icsk_accept_queue, req); inet_csk_reqsk_queue_drop_and_put(req->rsk_listener, req); @@ -817,6 +928,7 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, return inet_csk_complete_hashdance(sk, child, req, own_req); listen_overflow: + SKB_DR_SET(*drop_reason, TCP_LISTEN_OVERFLOW); if (sk != req->rsk_listener) __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMIGRATEREQFAILURE); @@ -832,7 +944,7 @@ embryonic_reset: * avoid becoming vulnerable to outside attack aiming at * resetting legit local connections. */ - req->rsk_ops->send_reset(sk, skb); + req->rsk_ops->send_reset(sk, skb, SK_RST_REASON_INVALID_SYN); } else if (fastopen) { /* received a valid RST pkt */ reqsk_fastopen_remove(sk, req, true); tcp_reset(sk, skb); @@ -846,7 +958,7 @@ embryonic_reset: } return NULL; } -EXPORT_SYMBOL(tcp_check_req); +EXPORT_IPV6_MOD(tcp_check_req); /* * Queue segment on the new socket if the new socket is active, @@ -860,11 +972,11 @@ EXPORT_SYMBOL(tcp_check_req); * be created. */ -int tcp_child_process(struct sock *parent, struct sock *child, - struct sk_buff *skb) +enum skb_drop_reason tcp_child_process(struct sock *parent, struct sock *child, + struct sk_buff *skb) __releases(&((child)->sk_lock.slock)) { - int ret = 0; + enum skb_drop_reason reason = SKB_NOT_DROPPED_YET; int state = child->sk_state; /* record sk_napi_id and sk_rx_queue_mapping of child. */ @@ -872,7 +984,7 @@ int tcp_child_process(struct sock *parent, struct sock *child, tcp_segs_in(tcp_sk(child), skb); if (!sock_owned_by_user(child)) { - ret = tcp_rcv_state_process(child, skb); + reason = tcp_rcv_state_process(child, skb); /* Wakeup parent, send SIGIO */ if (state == TCP_SYN_RECV && child->sk_state != state) parent->sk_data_ready(parent); @@ -886,6 +998,6 @@ int tcp_child_process(struct sock *parent, struct sock *child, bh_unlock_sock(child); sock_put(child); - return ret; + return reason; } -EXPORT_SYMBOL(tcp_child_process); +EXPORT_IPV6_MOD(tcp_child_process); |